The metathesis (or disproportionation) of cyclic olefins is a well known technique for preparing divinyl or other polyvinyl compounds. See Dragutan et al, Olefin Metathesis and Ring-Opening Polymerization of Cyclo-Olefins, John Wiley and Sons Limited, New York, 1985, pages 140 to 153, particularly pages 141 and 143. On page 141, the reaction of norbornene and ethylene in the presence of a cobalt molybdate catalyst to provide 1,3-divinyl-cyclopentane is mentioned and, on page 143, a metathesis catalyst, WOCl.sub.4.Sn(C.sub.4 H.sub.9).sub.4, is disclosed.
Polyvinyl compounds, particularly divinyl compounds (alpha, omega-dienes), are important precursors for a variety of compounds having two or more functionalities. These compounds find application as crosslinking agents and comonomers in resin and coating compositions.
While, as noted above, a large body of chemistry has been developed regarding the ring opening metathesis polymerization of norbornenes, the norbornenes have been essentially ignored as precursors for divinyl compounds on a commercial basis. This is somewhat surprising in that norbornenes have high ring strains making ring opening very favorable, and can only be explained on the basis of the present metathesis processes, which are prone to low conversions and selectivities.